Method of making a fermentable product from cellulosic and ligneous materials.



W. P. COHOE. MI'ITHUD OF MAKING A PERMENTABLE PRODUCT FROM CBLLULOSIU AND LIGNEOUS MATERIALS,

APPLIGAIIOH IILED JAN. 19,1910.

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- W. P. COHOE. METHOD OF MAKING A PERM )iTABLE PRODUCT FROM CBLLULOSIC AND LIGNECUS MATERIALS.

AIPLIGATKON FILED 1. m. 19.1910.

985,725, V Patented Feb."28,1a11. I I v 2a SSHEET2.

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' lNVENTOR ATTORNEYS.

i Unrzenn s-rrxrno rnrisnr orrrori.

WALLACE P. COHOE. OF TORONTO. ONTARIO, CANADA; I

METHOD OF MAKING A FERMENTAB LE PRODUCT FROM CELLULOSIC AND LIGNEOUS MATERIALS.

Specification of Letters Patent. Patented Feb, 28, 1911.

Application filed January 19, 1910. Serial No. 538.797.

wvhich it appertains to make and use the same.

My invention relates to certain new and uaoful improvements in obtaining a fermentable glueosclike productfrom cellulosic ma terial and ligncous material; that is to em.

from cellulose and from the lio'nine, or both,

' as the case may be, and especially from sawdust and other waste'wood products. such material being either in the untreated condition. or having been previously treated by an lllt'tllllplfilt. hydrolyzin; process.

Prior to my invention, it has been propoaed to treat sawdust and imilar waste. wood products with Snl'ftllults acid and with a mixture of Ftllfltl't'flls and sulfuric acidy and it has even been suggested, in some instances. that for the sulfuric acid employed in admixture with sulfurous acid there may he used a corresponding quantity of hydrochloric acid. In practice, however, for val'iOtts reasons, the arthas finally limited itself to the employment. of sullurons acid alone, and, in so far as 1 am aware, there is at present no commercial utilization of any othe' acid than sulturoux acid for the purposes in question.

The employment of sulfur-nus acid, either with or without an addition of sulfuric acid. is attended with the objection that the. h \'drolizcd product is quite dark and, furthcrmore, that the hydrol vzin; action is infurther emphasixee the relatively minor effect of sulfurous. acid as a hydrolyzing agent upon cellulose.

According to the process of the present in vention. by the employment of a weak 50111- tion of hydrochloric acid under proper conditions as the hydrolyzing agent a very much greater output of fcrn'ientablc product can be obtained from. the cellulose and lignin of the ligneous. material treated. carefully following the procedure here-ire after indicated. it is possible to obtain almost the maximum yield, and likewise to obtain a clear product of light color, which .is readily 't'ermentable. ln obtaining this product', it. is found that the hydrochloric acid has hydrolyzed not only the lignins. but also the eellulme, and tcts have shown that it is an cfiicicut hydrolyzer of cellulose per 2'. 6., cellulose whether arsociated with the lignins or not. A etriking and characteristic cxcnu'ilitication of the ad 'antagc of the enlploynient of hydrochloric acid in this regard is attorded by the circumstaiu'e that after awdu 1t or other wood waatc has been subjected to the lrvdrolyzing action of'a solution of sulfurous acid in the usual commercial -'a y. the residue may be further hydr0- lyzcd by subjecting it to the action of hydrochloric acid in accordance with the process herein described, so as to recover a large additional amount of fermentablc product. 4

Further tcature of my invention include the col ecting of the reaction gases from the mass that is being: treated with the weak solution of hydrwhloric acid and the circu lating of the gases through the mass as the operation proceeds. This circulation of the lll-Slll'ls' uniform action by preventing" stratitication and localization of the differ ent gustfi in the mixture. So also, my invention includes the feature of progressively withdrawing from the sphere of the reaction the fermentable or hydrolyzed products as they are produced, this withdrawal being found to largely facilitate the operation and to result in a greater output per unit of time. It is probable that the increased etliciency thus obtained in the hydrolyzing process is due to the fact that, by removing the hydrolyzed products or sugars either continuously or from time to time as they accumulate ii the 'eaction vessel, the balaneing or partial reversal of the hydrolyzing Indeed. by i rcact-iondue to mass action is prevented, thuallowing the formation of the sr' irsto go larly described.

In the. accompanying drawing, .l have illustrated, more or less diagramn at cally,

suitable forms of apparatus for carrying the invention into practice.

In the. drawings,- Figure 1 represents a central horizontal section of a rotary form of apparatus suitable for the purpose; Figs.

2, 3 and 4. represent in vertical section stationary forms of apparatus which may be. employed according to the particular requirements ofnse.

Althougln as hcreinbcfore indicated, my invention is applicable to the treatment of either cellulose or lignins per se, it will have its chief application in the treatment of sawdust and other waste wood products wherein cellulose is associated with the lignins, and the mode of operation incident to the practice of the invention \VlllllllQiCfOt'C he sutliciently indicated by reference to the treatment of sawdust. I i

la the socallcd dry treatment (dry cook of the sawdust or other waste wood product acted upon the amount of the dry onstituents of the material is first determined or approximately estimated. dust usually contains from twelve to titty per cent. of moisture. For the treatment of sawdustin the dry way there may he added to the sawdust a solution of hydrochloric acid of such strength that there will be present in the mixture from {,{J to Q'j'b of HG! based on the weightof the dry constituents of the sawdust. To this there is then added enough water to bring the total weight of the solution up to the weight. of the dry constituents of the sawdust. The water may he added in a vaporized condition. In the socallcd wet treatment. (wet cook) the same relative proportion of Iltll to the weight of the dry constituen s of the sawdust is cmployml but there is added an amount of watersuilicient to bring the weightof the water up to from four to five times the weight of the dry constituents of th sawdust.

The apparatus shown in Fig. 1 is parli ularlv adapted to the treatment. ofthe sawdust by a dry cook. ('lcnerally stated, the apparatus. shown in Fig. 1'. consists of a rotary cylinder A provided with a charging l l l l l i l 'l'ml' l5 and with a blow-oil pipe (I ha\in; a

controlling valve a, T he. cylinder is pro- ;-d internally with a lining of a material 6 resistant to the action of hydrochloric. acid, as, for instance asbestos impregnated with "bakelite a product resulting from the condensation of phenols with formaldehyde. The cylinder is further provided with hands or tires (Z and is mounted to rotate in any suitable manner upon supporting rolls f. its rotation being etl'ected by any appropriate driving mechanism, not shown. The cylimler is likewise provided with an axial pipe D, which may he made of any suitable acid-resisting material, such as hattelite; or it may be of metal coated with hakelite. This pipe is provided with a suitable number of perforations along its length. if desired, the cylinder may be further providcd \vitl longitudinal wings along its cvlindrical side walls for lifting and dropping the material during the rotation of the ap paratus. therefore, a drum digestcr. Its axial pipe D is intended to he stationary during the revolution of the drum, and a stutlin; box *1 is provided whose main elcmcnts may conveniently he mane of bakelitc and graphite, or of metal lined with bakclitc or similar acid-proof enamel.

in operati n. the drum dig-ester may be tilled three-tourths full of dry sawdust wl crcupon live steam umler say sixty-live pounds pressure is admitted from the steam pipe I into the axial pipe l) and thence into the lilil To this steam will he added the hytlr-ochloric acid which may he admitted through the pipe ti. 'lhe i'ligestcr may be. rotated duringthe operation and the treatment will be continuedumil the contents of the. dig ster reach a temperature of about 145 (Land condensation and reaction have resulted in the .t'm'matiou of a solution of sugars in the sawdust. The attainment of this temperature indicates the completion of the operation and the admission of teanl is thereupon interrupted and the digester is brought into the position indicated in Fig. I. that is to say. with the blow-otl' pipe (I at the top; ll opening the valve 11 the gaseous and vaporous contents of the digester may be blown oil and may advautageouslr be taken into condensers and absorbing towers so as to 'u!!(llli l and save the acetic. acid. h vdrochloric a id. 'turt'urol and the like contained therein. The contents of the digester may then be dumped through the dun|pin, door ll. and the "lln'():-(?-lll((! product may then be extracted by means of hot: water. It is found that from to 29", of the dry sawdust is converted into lermcntable glucoselike products hi this truzltnnnt, the most favorable results as to yield being obtained b using a solution containin; from 1.1% to 2'); nt' liYtll'm-lllnl acid. The \"l'l |7s resultin; from the extraction of the digc ted mass-arc light in color and notdark (almost black) as is the case when sulfurous and sul- The :IPPHIZli'U-S' shown in Fig. 1 is,

. to provide a space 1 which communicates by gestcr preferably in the fiiroportions best I the injecting action of the steam jet, which furic acids are employed. For this reason they may be clarified much more easily. and 85 high as 80% and upward of the yield of converted products isvfermcntable to ethyl alcohol. It is found that the residue left over after extracting the-glitcose-likc prodnot from the mass resulting from the. first operation in the digester may be to advantage subjected to a-turther treatment, in the same way. and that an additional quantity of the glucose-like product may be obtained therefrom which may in like manner be extracted by means of hot water. The first treatment may, as stated, be with sulfin-ous acid if desired. This successive treatment of the same mass enables the yield. ot the glu- C05C-llh0 product to be largely increased, thereby giving correspondingly improved commercial results.

The form of apparatus shown in Fig. 2 is particularly adapted for continuous working and for a wet cook. The digestcr shown. in said figure is of thestationary type consisting of a vertical shell A havinga lininp b resistant to hydrochloric acid. The digestcr is provided above with a charging door B and below with a dumping door I) and likewise has at its lower portion a perforated bottom H which may conveniently be of conical form so as to facilitate the final discharge of the iii-ass after treatment. and

a pipe I! with a suitable trap whereby any portion of the liquid collecting inthe space (I may be drawn oil from time to time. Steam may be admitted through the pipe l and is conveyed upwaidly through an inner portion of the digcstcr. The mass of sawdust together with the weak solution of hydrochloric acid is charged into the d1- adapted for the wet cook, as hercinliefore iiidicated and a ('HK'Jiltlllflll of the liquid is maintained through the mass by reason of earries the liquid as it drains through the perforated bottom through the pipe l). discharging it; upon the upper surface of the mass, through which itagain descends into the space ff. As the solution of glucose-like product accumulates. the solution can lie tap icd ofi in part from tinic to time thereby Withdrawing the tapped-off portions from the sphere of the reaction. The losses in solution are supplied by condensation of the sham and by appropriate additions of hydrochloricacid which may be taken in through the steam pipe or otherwise supplied so as to maintain the desired pcrccntafc of" h \-'di'ochl0i'i: acid for the efiicicnt operation of the process In the form of apparatus shown in Fi". 15 which is likewise intended to be used for a l wetcook. the upright, digcster A having a lining I) and having charging and dumping doors B 8* is designed to be operated atatmospheric pressures and issurmounted 'with a condenser I, wLch may conveniently -mitted through a. pipe F terminating in a perforated coil at the lower part of the digester as shown. In fact. the initial heating of the mass may be supplied wholly by m the steam inp cted through the pipe 1*- if desired.

In the form of apparatus shown in Fig. 4 the upright digester A" with its lining b charging door B and dumping door B is likewise preferably provided with a steam packet J and with a steamin Jecting pipe F terminating in a perforated coil at the b0ttom of the dig-ester. In'this instance, the digester may he used to treat; the sawdust in accordance with the dry cook method, if desired and, in fact, this particular form of apparatus is preferred for the dry cook method wliena rotating digester is not; employed. The operation is conducted at a high temperature and under high pressure as in the. rotary digester and the reacting gases of the dry cook are withdrawn through the conduit K by means of a pump L and are I'OlIiU'OtlUL'Cd through the pipe F into the bottom of the digester, thus obtaining the desired circulation. On opposite sides of the pump are provided the usual check valves 1 and the tension or the gases withdrawn and reinjected is raised by passing them downward through the tubular heater M having a series of pipes inwhich are heated externally by steam entering through the pipe 22. and issuing at the pipe n.

.\s hei'einhet'ore indicated. it; will of course be undersii'iod that wherever any of the surfaces of the apparatus are brought into contact with the hydrochloric acid they are to be suitably protected by an enamel or other coating of sutlicient resistance to bydrochloric acid to protect them against corrosion. Furthermore. wherever, in the various forms of apparatus a dry cook or a wet cook is employed, the prescribed conditions for obtaining the best results are preserved; that is, the preferred minimum amount by weight of the solution with respect to the dry constituents of the saw dust is used when a dry method is followed and the preferred maximum weight. of the solution with respect; to the dry constituents of the saw dust is employed when the .wet

method is follmved. It will furthermore be noted that in either event. the employment of a high temperature and a high pressure is of advantage, especially in hastening the reactions and that We features of withdrawing the glucose-like products from time to time as they are formed, the continuous treatment of the mass and the re-trcatment of residues from prior operations are of advantage whether the dry method or the wet. method practieelil.

llaving thus described my invention, what I .:laim isi l". in the manufacture of glucosedike products from woody material such as sawdust and the. like, the process which comgether with h \"dr(uhlo1io acid into the mass tobe hydrolyzed until a solution of sugars is formed: substantially as described.

3. In the manufacture of glucose-like in a dry condition by injecting steam toproducts fronrwoody material such as sawdust and the like, the process which comprises hydrolyzing such material in a dry condition by injecting hydrochloric acid into said material by means of a current of steam i until a solution of sugars is formed; sub stantially as described.

4. The process of producing glucose-like products from woody material such as sawdust and the like, which comprises exposing the same to the action of a current of steam carrying a volatile hydrolyzing acidnntil a mass of sugary liquid accumulates, sugary liquid being removed from time to time to prevent. interference vrith the hydrolyzing reaction; sul'istautially as described.

The process of producing glucose-like products from woody material such as sawdust and the like. which comprises exposing a mass of s ch material to the action of a current of steam carrying a volatile hydroiyzing a id until a n'iass of sugary liquid :m'umulatcs. portions of such sugary liquid being removed from time to time to prevent i interference with the hydrolyzatmn; sub- I stantially as descrilicd.

prmlucts a unis-s of such material to the action of a current of steam carrying hydrochloric acid until a mass of sugary liquid accumulates, portions of such sugary liquid being removed from time to time to prevent inter- 't'crcnce with the lrrdrolyzation; substantially as described.

7. The process of producing glucose-like products from woody material such as sawdust and the like, which comprises hydrolyzing such material in a heated condition by t.r .atin; it with a hydrolyzing acid, and positivcty circulating the gases resulting from the hydrolyzat-hin through the material undcrgoiug treatment; substantially as described.

S. The process of producing glucose'like products from woody material such as sawdust and the like, which comprises hydrolyzing such material in a heated condition by treating it with a volatile hydrolyzing acid, and positively circulating the gases resulting from the hydrolyzation through the material undergoing treatment; sub stantially as described.

'lhe prm-ess at producing glucose-like products which comprises hydrolyzing a mass of such material in a heated condition by trcatuu-nt. with a volatile hydrolyzing acid removing the reaction gases from thesphere of reaction. and fircing the gases thus rcn'iovcd back into the mass of material undergoing treatment; substantially as dc scribed.

10. The process of producing glucose-like products which comprises hydrolyzing a mass of such material in a heated condition by treatment with dilute hydrochloric acid, removing the reaction gases from the sphere of reaction and forcing the gases thus re-' moved back into the mass of material undergoing treatment; substantially as described.

.11. The process of producing glucose-like products which comprises hydrolyzing a mass of such niatcrial in a heated condition by treatment with dilute hydrochloric acid, removing the reaction gases from the sphere of reaction, and injecting the gases thus removed into the mass undergoing treatmentby means of a current of steam; substan tially as described.

12. The process of obtaining a fermentable glucose-like productfrom cellulosic and ligneous material, which consists in su'3 ectiug it. to the hydrolyzing action of a weak solution of hydrochloric acid, the minimum weight of the solution not glittering substantially from the weight of the dry constituents of the mass; substantially as described.

13. The process of obtaining a fermentable glucose-like product from cellulosic and ligneous material, which comprises first ef- 6. The irocess of producing glucose likez t rom woody material such as sawdust and .the like, \vhic. comprises exposing feeling a partial hydrolyzation hereof and extracting the product thus made, and thereafter subjecting the residual material to the hydrolyzmg action of a weak solution of hydrochloric acid; substantially as described.

14. The process of obtaining a ferment able glucosedike product from cellulosic and ligfieous material, which comprises first ef- In testimony whereof I affix my signature, ferfiing a partial hydrolyzavtion thereof with in presence of two witnesses.

su 'urous acid and oxtractin the product; 1'

thus made, and thereafter lbjecting the WALLACE OOHOE residual material to the hydrolyzing action of a weak solution of hydrochloric acid; substantially as described.

Witnesses:

E. MERNER, H. CHRISTMAN. 

